SYSTEM SPECIFIC FUNCTION CONTROL IN A MOBILE RADIO DEVICE

Abstract: A radio device, such as a personal computer with a radio modem (1) or a cordless telephone (10) arranged to operate on first and second radio communications systems (3, 4, 14, 15). The device has registration means (37) for registering on the first and second systems respectively for transmission or receipt of traffic on that system and user actuation means (6, 7, 20) for initiating an operation of the device, wherein the operation initiated is dependant on the system on which the device is registered.

Description: SYSTEM SPECIFIC FUNCTION CONTROL IN A MOBILE RADIO DEVICE Field of the Invention This invention relates to a radio device arranged to operate on different radio communication systems. The radio device may be, for example, a notebook type of personal computer with a radio modem or it may be a pager or a personal communicator such as a cordless handset. Separately and in addition, the invention relates to a combination of first and second radio devices. Background to the Invention Radio devices are becoming consumer items and more and more varied in functionality. Personal computers are available with radio modems which can transmit and receive electronic messages to and from a radio system and between each other. Messages are displayed on a screen and entered using a keypad or a stylus. Addresses can be called up from memory for defining the destination for a message. Icons can be displayed on the screen which operate as buttons to initiate functions of the device through operation of a mouse or a stylus. With demand for smaller and smaller devices, space on the housing of the device for locating buttons is limited. Equally, space on a screen for displaying different icons is limited. As functionality of a radio device increases, its operation becomes more complex and confusing to a user. There is a need for increasing the functionality of a radio device in a small housing with minimum action required by the user to establish the functionality. In the more specific field of cordless telephones, US Patent 4745632 describes a wireless mobile telephone communication system in which a conventional wireless telephone unit is integrated with a conventional mobile telephone unit to provide remote capabilities. The communication system purports to allow the driver of a mobile telephone equipped vehicle to use a low cost wireless telephone unit to receive calls while away from the unattended vehicle using the remote wireless handset. It would be desirable in such an arrangement to use, for the wireless telephone unit, a radio device of a type that has registration means for registering on a communication system, for example a CT 2 cordless telephone. A CT2 handset must register itself onto a base station in order for it to operate through that base station. This is performed via a registration procedure automatically carried out by the portable unit when the user selects whichever base station he desires. It would be useful to use such a handset as a remote handset for a mobile radio such as a Motorola CQM6000 radio or a trunked Motorola radio according to British Standard MPT1327. It would also be useful for the radio device to be operable on a separate communication system, such as its own intended CT2 communication system. A cordless telephone handset is not normally suited to operation on two such systems. Summary of the Invention According to the present invention, a radio device is provided which is arranged to operate on first and second radio communication systems, the device having registration means for registering on the first and second systems respectively for transmission or receipt of traffic on that system and user actuation means for initiating an operation of the device, wherein the operation initiated is dependant on the system on which the device is registered. Depending on the system into which the handset is registered, certain user actuation means, for example a button or location of a mouse on a display, can have its function dictated by the system onto which the device is registered. The function of the user actuation means may, for example, change between accessing different services such as different information subscription services. In the case of a cordless telephone handset the user actuation means may be a button which has a push-to-talk function when the handset is operating as a remote wireless handset of a trunked radio system, and some other function when the handset is operating as a cordless handset of a cordless telephone system. Cordless telephone systems do not normally require PTT buttons, as they provide full duplex operation, whereas private mobile radio systems are frequently half duplex and require instant access to the channel through the PTT button. Almost any button of a cordless handset can be used for this purpose, for example a cordless handset may have a "send button" for initiating the dialling of a pre-entered telephone number. This button can be used as a PTT button. More preferably, the handset is provided with a button which in the cordless telephone mode of operation, acts as a mute button for muting the microphone and in the private mobile radio mode of operation acts as a PTT button. The advantage of the use of such a button is that for both modes of operation it is useful to position such a button on the side of the handset in an easily accessible manner. Such a button may be used frequently during the course of a telephone or radio conversation and in both cases requires positioning in the same ergonomically selected position. Other functions of the buttons may change depending upon the system to which the device is registered, such as the function of keys on the key pad and the information that is caused to be displayed on a display. Brief Description of the Drawings Fig.l shows a radio device according to the present invention in communication with a radio system. fig. 2 shows a combination of a radio device and a mobile radio in accordance with the present invention. Fig. 3 shows details of the radio device of Fig. 2. Fig. 4 shows details of the mobile radio of Fig. 2 and Fig. 5 shows an exchange of commands between the radio device (hand set) and mobile radio of Fig. 2. Detailed Description of the Preferred Embodiment Referring to Fig. 1, a radio device is shown in the form of a notebook computer 1 with radio modem 2. The computer 1 communicates with two radio systems 3 and 4 having databases 3' and 4' via at least one base station 5. The different systems 3 and 4 could communicate through different base stations. The computer 1 has a screen 6 on which icons are activated by a stylus 7. As an example of operation, the database 3 provides horse racing information and the database 4 provides stock market information. In operation, a user register who has subscribed to the horse-racing information service registers onto system 3 by transmitting a user identification number and performing authentication. The system 3 identifies itself to the computer 1 and the computer 1 automatically configures its screen 6 to display horse racing information from the system 3 (as shown on the left hand side of the screen 6) and to accept inputs relating to that system, such as selection of racecoureses and placing of bets. If, now, the user of the computer registers onto the system 4 by transmitting a new and different user identification number and performing authentication, the system 4 identifies itself to the computer 1 and the screen 6 instead shows stock market information as shown on the right hand side and accepts inputs relating to the system 4. The reconfiguration of the screen 6 is automatic according to the system on which the computer 1 has registered. Similarly, the reconfiguration of the input device (screen 6 and stylus 7) is automatic according to the system on which the computer 1 has registered. Referring to Fig. 2, a radio device in the form of a CT2 handset 10 is shown, communicating with a mobile radio 11 which comprises a CT2 interface 12 and a trunked mobile radio 13. The CT2 interface 12 is a private CT2 base station modified in a manner described below. The mobile radio 13 is a Motorola CQM6000 radio, but could be any private mobile radio (PMR). The mobile radio 13 communicates with a trunking system base station and controller 14. The handset 10 has a mute button 20 on its side face. Also shown in Fig. 2 is a standard CT2 base station 15 connecting to a public switched telephone network (PSTN) 16. A CT2 handset 10 must be registered onto a particular system before being it is able to be used. For private base stations this is a simple operation involving a button on the base station 12, 15 and a code entered into the handset (the code being supplied with the base station). The handset is then ready for use on that particular system. However as the same handset can be used on many different systems (up to four public and eight private) it must switch between these. Once it has been registered onto all the systems required by the user, the handset can be switched between them by simply keying in the number of the system required. The handset has effectively twelve channels for the user to choose from. Only those that have been registered to systems can actually be used. This also means that once a channel has been selected, the handset 'knows' which system it is logged onto. In the present preferred arrangement, a CT2 handset 10 is linked via a private base station interface 12 into a mobile radio 13 for use on a trunked radio system 14. This arrangement requires certain novel functions to be considered for the CT2 handset 10, primarily a PTT function. For this purpose, in the process of the handset registering on the system 11 before being allowed to use that system, there is some interaction during the registration process. During this initial stage of system set-up, the handset 10 is informed by the base station 12 that it is in fact talking to a mobile unit 13 and not, for example, an ordinary private base station 15. Accordingly, the handset should attach a marker to this effect to whichever channel is assigned. This marker is used as an identifier in the software in the handset 10. If this marker is detected when a channel is selected, the software in the handset 10 can redefine the function of 20, its mute button as appropriate. Referring to Fig.3, a schematic diagram of a CT2 portable handset is shown. The handset comprises an antenna 21, a transceiver 22, a time division duplexer 23, a voice coder and decoder (codec) 24, a gain adjustment unit 25, a side tone adjustment element 26, a volume control 27, a ringer control 28, a microphone 29 and a loudspeaker 30. Connected to the transceiver 22, the time division duplexer 23 and the coder 24, via a bus 35, are a keypad 36 a microcontroller 37 and a display 38. The keypad 36 is shown as including the mute button 20. In a normal registration operation, a registration initiation command is entered via the keypad 36, which causes the microcontroller 27 to send a registration command to the transceiver 22, which is transmitted to the base station 15. The base station 15 sends a pseudo-random number to the handset 10. The microcontroller 37 performs an authentication algorithm on this number by combining it with a registration ID and sends this back to the base station 15. The base station 15 compares the received data with the transmitted data to identify that the authentication algorithm has been correctly performed and at the same time extracts the identification ID of the handset 10 for billing purposes. The base station 15 sends an acknowledgement to the handset 10 that registration has occurred. The handset 10 can now transmit to the base station or receive telephone calls. The elements 21 to 30, in their hardware form, are standard elements c ς a CT2 portable handset. Voice entered into the microphone 29 is coded in the codec 24, inserted into appropriate time slots by the time division duplexer 23 and transmitted by the transceiver 22 through the antenna 21. Radio signals from the base station 15 are received at the antenna 21 and demodulated in the transceiver 22. The time division duplexer 23 extracts the desired time slots from the received signal and sends the extracted data to the codec 24 which decodes voice from the data and supplies it to the volume control unit 27 for outputting from the speaker 30. A novel feature of the preferred embodiment of the invention is that, in the course of the handset 10 registering on the mobile unit 11 via the CT2 interface 12, when acknowledging the registration procedure, the CT2 interface 12 sends a special identifier identifying that the CT2 interface 12 is an interface for a private mobile radio. This identifier is received in transceiver 22 and supplied to controller 37. On receipt of this identifier, controller 37 reconfigures the functions that it associates with the buttons and key pad 36. It can also reconfigure its association with the display 38. In "normal" operation, that is to say when the CT2 handset is operating as a cordless telephone unit registered on base station 15, button 20 operates as a mute button. When the user presses button 20, microcontroller 37 recognises this input and effectively disables the downlink operation of codec 24, that is to say any voice or noise entered into microphone 29 is not coded by the codec 24. On receipt of the special identifier identifying that the handset 10 is registered on a Motorola radio system, controller 37 identifies button 20 as being a push-to-talk button. In this configuration, pressing of button 20 causes immediate keying up of the transmitter part of transceiver 22 (in the appropriate time slots) for immediate transmission of voice from the microphone 29. From the user's point of view, the button has the opposite function. Instead of muting the microphone, it now opens the channel. If preferred, the polarity of the button can be reversed, that is to say it opens the channel when released and releases the channel when pressed. This may be less confusing to the user, but is not the normal action of a PTT. It is more advantageous that the active pressing of the button should access the channel. In this way, the channel is only occupied when the button is pressed. The mute button is a particularly advantageous button to use for a PTT function due to its position on the handset, naturally accessible even while holding the handset to the user's face and because its function is redundant in half duplex operation. In the PMR mode of operation, pressing the PTT button 20 causes a message to be transmitted from the handset 10 to the mobile unit 11 for decoding by the interface 12 and causing a PTT activation in the mobile radio 13. This message signal can be transmitted from the handset to the interface 12 in one of two ways. The message can be incorporated into the audio part of the CT2 common air signalling platform or the message can be incorporated into the data part of that platform. The CT2 interface 12 and mobile radio 13 can be separate units in a back-to-back arrangement as shown in Fig. 2, with traffic passing between the units and with a PTT control line passing from the interface 12 to the mobile radio 13. .Alternatively, the transceiver parts of the units 12 and 13. i.e. the CT2 transceiver and the mobile radio transceiver, can be incorporated into a single unit. This is illustrated in Fig 4. Fig. 4 shows details of the mobile unit 11 and comprises an antenna 40 and an antenna switch 41, a transceiver 42, a time division duplexer 43, a codec 44 and a controller 45. The case will be considered where the PMR system is a time division duplex system with voice coding such as the Pan European TETRA system. During transmission, coded speech is received from the handset 10 on the CT2 channel through the antenna 40, received at the transceiver 42 and decoded to baseband. Received data is extracted in the appropriate time slots by time division duplexer 43 and passed to codec 44. Codec 44 transcodes the voice (if necessary) from the CT2 coded form to the TETRA coded form and passes the re-coded speech to the time division duplexer 43 for insertion into TETRA time slots and transmission by the transceiver 42 on a TETRA radio channel through the antenna 40. Traffic received from the PMR system 14 is handled in reverse. Other arrangements can be considered, for example where no coding is used on the PMR channel. In this case, codec 44 decodes received traffic from the handset 10 and outputs digitised or analog voice which bypasses the time division duplexer 43 and is simply transmitted by the transceiver 42. Received analog or digitised voice is handled in reverse, coded by the codec 44 and transmitted in CT2 time slots and channels by duplexer 43 and transceiver 42. In each case, controller 45 is arranged to receive a registration request from a CT2 handset 10 and in response to that registration request it is arranged to confirm registration and include a special system identifier identifying that the current system is a PMR system. Different identifiers may be provided for other systems such as different types of PMR system, or cellular radio systems or indeed different types of cordless telephone system. Depending on the system to which the handset is registered, the handset will itself reconfigure its buttons and/or its display to suit the appropriate system. Fig. 5 illustrates the exchange of registration commands between the handset 10 and the mobile unit 11, that it is to say between the controller 37 and the controller 45. The left hand side of Fig. 5 represents the handset 10 and the right hand side represents the mobile unit 11. The handset 10 initially transmits a call set-up command which is received by the mobile unit. The mobile unit, via its interface 12 sends a confirm registration command which includes the system index. The handset 10 associates the system on which it is operating with the index, for example identifies whether it is a trunked PMR system or a telephone system. Assuming that the handset 10 is simultaneously registered on two different systems, the user can select the system on which he wishes to make a call by pressing an appropriate key or key combination. In the case of a telephone system, the user can now enter a telephone number and a press a "send" key. This will initiate a normal CT2 cordless telephone call. Should the user wish to make a PMR transmission he may enter a PMR mode by pressing an appropriate key combination and in this mode he merely needs to press the PTT button 20 for immediate access to the channel. PMR mode may be entered by the user manually at the handset or it may be initiated by the mobile unit 11 at the time when a group call is set up. .Alternatively, in the case where handset 10 operates on only one system, the mode of operation of the handset is automatic dependent on the system onto which it is registered.

Claims: Claims 1. A radio device (1, 10) arranged to operate on first and second radio communications systems (3, 4, 14, 15), the device having registration means (37) for registering on the first and second systems respectively for transmission or receipt of traffic on that system and user actuation means (20) for initiating an operation of the device, wherein the operation initiated is dependent on the system on which the device is registered. 2. A radio device according to claim 1, wherein the first system (15) is a radiotelephone system and the second system (14) is a private mobile radio system. 3. A radio device according to claim 2, wherein the user actuation means (20) performs a push-to-talk function when the device is registered on the second system and performs a different function when it is registered on the first system. 4. A radio device according to claim 3, wherein the device has a microphone (29) and the actuation means (20) selectively mutes the microphone when actuated when the device is registered on the first system. 5. A radio device according to claim 1 or 2, wherein the device (10) comprise a display (38) and wherein the actuation means causes first and second sets of indications to be displayed when the device is registered on the first and second systems respectively. 6. A combination of first radio device (10) and second radio device (11), the first radio device being operable in a first mode and a second mode and having registration means (37) for exchanging registration information with a first radio system in the first mode and exchanging registration information with the second radio device in the second mode, the first radio device further having user actuation means for initiating an operation of the first radio device, wherein the operation initiated is dependent on the mode of operation of the device.

Inventors: ADEY MARK EDWARD, VAN DEN HEUVEL ANTHONY PATRICK, ADEY, MARK, EDWARD, VAN DEN HEUVEL, ANTHONY, PATRICK
Applicants: ADEY MARK EDWARD, HEUVEL ANTHONY PATRICK V D, MOTOROLA INC, ADEY, MARK, EDWARD, MOTOROLA INC., VAN DEN HEUVEL, ANTHONY, PATRICK
Application year: 1994
Main classification: H04Q7
IPC codes: H04W88